1. Field of Invention
The invention relates to bicycle brake systems and more particularly to a mechanism for quickly adjusting tightness of a brake cable (i.e., loosening the brake cable for a subsequent removal of tire) in a caliper brake of bicycle with improved characteristics.
2. Description of Related Art
A conventional caliper brake of bicycle is shown in FIG. 1. The caliper brake is implemented as a single pivot side-pull brake. In a normal condition, a brake cable 3 is held tight. It is seen that a distance between two opposite brake pads 13 and 14 is less than a width of a tire 4. The caliper brake comprises a brake cable loosening and tightening device 10 at one end of a second arm 120 which has a second brake pad 13 at the other end. The caliper brake further comprises a first arm 110 having a lower end provided with a first brake pad 14 opposite the second brake pad 13 and an upper end with a cable housing 11 provided thereat. Both arms 110, 120 cross at a pivot (not shown). A brake cable 3 passes the cable housing 11 to terminate at the brake cable loosening and tightening device 10. A fastener 2 has a nut 21 for fastening the brake cable 3 at the cable housing 11.
For removing the tire 4 for repair or replacement, a person may manipulate the brake cable loosening and tightening device 10 to loosen the brake cable 3. As such, both brake pads 13, 14 move laterally away from each other. The manipulation of the brake cable loosening and tightening device 10 can be stopped if the distance between the brake pads 13 and 14 is greater than the width of the tire 4. Thereafter, the person may easily remove the tire 4.
But this is unsatisfactory for the purpose for which the invention is concerned for the following reasons:
The brake cable loosening and tightening device 10 is exposed. Hence, it tends to loosen or damage due to contact with foreign objects. Further, its appearance is not aesthetic. Furthermore, its operation is not smooth or even uneasy. Thus, the need for improvement still exists.